There are specific reversals like "bad" for "good", but they're much
more culturally, lexically or situationally restricted.

All the obvious Gricean accounts that I can think of
seem to be invertible, which is not consistent with the facts. So
I did what I usually do in such cases: I asked
Ellen Prince. She came back with a connection to
a classic observation by Edward Sapir:

In a paper from way back when ('Grading' I think), Sapir noted
that the noun for a scalar property corresponds to the adjective
at the positive end -- so one's beauty can be zero, meaning one
is ugly, but one's ugliness being great doesn't make one beautiful.
Likewise, height (< high) is unmarked for how high/tall one is
but shortness must be short; one's intelligence can be so low
that one is stupid but one's stupidity can never get high enough
to make one intelligent, etc etc etc.

As Ellen suggested, the problem with "reverse sarcasm" is probably connected
to this, somehow: sarcasm can reduce the implicit
value of a positive scalar property to the point that it turns into
a negative one, but doing the same thing to a negative scalar property
doesn't turn it into a positive one.

[Update 10/28/2003: several people, including Ellen Prince and
Prentice Riddle,
have supplied examples where negative-to-positive reversal seems to work.
Prentice's contribution was personal and convincing: "You spent two days in Monterey? How awful!"

But I still think that there's a difference here. His example reminds me of
one of my college roommates. I can remember John tasting the taramasalata at the Greek restaurant across the street from our dorm, and saying "Mmm, disgusting!" with a beatific smile on his face. He was known for this sort of thing, and it was generally regarded as weird. I'm pretty sure that *he* thought it was weird, and did it precisely because it doesn't really work by the normal rules of conversational interpretation, though it seems like it should.
(I don't mean that Prentice is weird. His example seems normal, it just reminds me of an old friend's long-ago odd jokes).

In general, I somewhat mistrust my intuitions on this, and recognize that it
might be a "mind set" problem like the old quantifier dialect investigations.

It's also been pointed out to me that "reverse sarcasm" is a pretty bad term for this phenomenon, since sarcasm usually doesn't involve inversion of scalar predicates, and the scalar-predicate-reversal cases need not have the contemptuous or mocking tone required for sarcasm.

So to sum up, the cited facts are somewhat wrong, and the proposed name for the phenomenon contains at least two mistaken presuppositions. Oh well, feel free to apply for a pro-rata refund of your subscription fees :-).]